What affects stability of nano silica powder suspendcion?
Nano silica powder has its wide range of applications because of its peculiar function in the light, heat, electricity, magnetic and other aspects In many processing techniques, the production process requires the powder to be uniformly and stably dispersed in the liquid medium. However, due to the large surface of the ultrafine powder surface, the surface can make the particles attract each other and have a tendency to instability, this tendency to produce agglomeration of particles and affect its application effect. So the dispersion technology is ultra-fine powder technology in the key technology.
The smaller the viscosity value, the better the suspension. We use the rotor viscometer to determinate how does different pH value and under addition of different organic suspending agent and dispersant dosage affect the silica viscosity value. Through the viscosity value to infer the conditions under which the best suspension of silica
Because of the many types of barren material, so the type of dispersion medium acidity and surface modification, the requirements of the active agent are not the same.Now scientific research, production and the most effective barren Suspension measures are: (1) Control the media PH value (2) Add the right amount of organic suspending agent
Silica in the acidic or alkaline medium can produce glue.In the glue solution, the change of hydrogen ion concentration will make the diffusion layer changes, resulting in increased or decreased potential, slurry viscosity will change, suspension Will also change. The use of organic colloids and surfactants as a suspending agent for barren matter is also a commonly used method. Since this gum is a macromolecule compound, when these substances are added, the silica colloid will stick to the molecular chain of the surface active material, and the weight of the chain becomes large and precipitates. When added as appropriate, the added material will form a granular structure and silica gel particles to form a protective film on top, silica particles are not easily collapsed by the collision, thereby enhancing the stability of the material